Various embodiments of consumer-operated coin counting kiosks are disclosed in, for example: U.S. Pat. Nos. 5,620,079, 6,494,776, 7,520,374, 7,584,869, 7,653,599, 7,748,619, 7,815,071, and 7,865,432; and U.S. patent application Ser. Nos. 12/758,677, 12/806,531, 61/364,360, and 61/409,050; each of which is incorporated herein in its entirety by reference.
Many consumer-operated kiosks, vending machines, and other commercial sales/service/rental machines discriminate between different coin denominations based on the size, weight and/or electromagnetic properties of metal alloys in the coin. With some known technologies, a coin can be routed through an oscillating electromagnetic field that interacts with the coin. As the coin passes through the electromagnetic field, coin properties are sensed, such as changes in inductance (from which the diameter of the coin can be derived) or the quality factor related to the amount of energy dissipated (from which the conductivity/metallurgy of the coin can be obtained). The results of the interaction can be collected and compared against a list of sizes and electromagnetic properties of known coins to determine the denomination of the coin. In other known technologies, a coin can be rolled along a predetermined path and the velocity of the coin or the time to reach a certain point along the path can be measured. The measured velocity or time is a function of the acceleration of the coin which, in turn, depends on the diameter of the coin. By comparing the measured time or velocity against the corresponding values for known coins, the denomination of the coin can be determined.
In some applications, however, the coins are closely spaced such that the velocity or interaction of a coin with the electromagnetic field is affected by the presence of another coin. As a result, coin counting mistakes may occur, resulting in possible losses for the kiosk operator. Accordingly, it would be advantageous to provide robust coin discrimination systems and methods that would work reliably for the coins that are spaced closely to other coins.